DAVID Mackay is free to play in Adelaide's round 15 match against Carlton after the AFL Tribunal cleared him of any wrongdoing in a collision with St Kilda youngster Hunter Clark.

After listening to more than two hours of evidence in an often testy case, the three-member jury of Paul Williams, David Neitz and Richard Loveridge took an hour to reach their decision.

>> WATCH THE INCIDENT IN THE PLAYER BELOW

Chairman Geoff Giudice said in summary that Mackay's "conduct was not unreasonable" in the collision that left Clark with multiple fractures to his jaw.

Mackay said he was relieved with the outcome.

"All week my thoughts have centred around Hunter (Clark) and his wellbeing," Mackay said.

"It was never my intention to cause any harm, I was only trying to win the ball, so I wish him nothing but the best moving forward."

Mackay insisted throughout the case his intent was always the ball and he never attempted to bump Clark.

"I thought I would get to the ball first for the whole period of time," Mackay said in his evidence.

"At no stage did I take my eye off the ball, believing I was going to be first to it."

>> ALL THE TRIBUNAL ACTION AS IT HAPPENED

Mackay pointed to the fact his right arm was limp at the point of impact and his hands were still down attempting to gather the ball.

Defence lawyer Andrew Culshaw said Mackay got to the ball 0.04 seconds after Clark did, making it a genuine contest.

"You have two incredibly brave players going full tilt at a loose ball," Culshaw said.

"This was a 50-50 ball.

"There is nothing unreasonable about a player going hell for leather for a 50-50 ball.

"This was an accident, a pure football collision.

"David Mackay's conduct was not even close to unreasonable."

The case was a long one, with evidence also given from an Adelaide data and football analyst, as well as a biomechanical expert to help clear Mackay.

In St Kilda's medical report submitted to the AFL, it confirmed Clark would miss 30-plus days of training and would be out for 6-8 weeks in total.

AFL counsel Jeff Gleeson argued the incident was avoidable and that Mackay's actions were unreasonable, knowing that hitting a contest at that speed it was likely high contact would occur and injury was almost inevitable.

"The potential for injury was frightening," Gleeson said.